Review Index:

Drobo Third Generation USB 3.0 4-Bay Storage Array Review - Simple and Speedy

Subject: Storage
Manufacturer: Drobo


Drobo is frequently referred to as ‘the Apple of external storage products’. They got this name because their products go for the simplest possible out-of-the-box experience. Despite their simplicity, the BeyondRAID concept these units employ remains extremely robust and highly resistant to data loss in even the most extreme cases of drive failures and data loss. I reviewed the DroboPro 8-bay unit over 5 years ago and was so impressed by it that I continue to use one to this day (and it has never lost data, despite occasional hard drive failures).

Over those past 5 years since our review of the DroboPro, Drobo (then known as Data Robotics) has also had a bit of an Apple story. Their original CEO started the company but was ousted by the board in late 2009. He then started Connected Data in 2011, quickly growing to the point where they merged with Drobo in 2013. This was not just a merger of companies, it was a merger of their respective products. The original Transporter was only a single drive unit, where Drobo’s tech supercharged that personal cloud capability to scale all the way up to corporate environments.

Many would say that for that period where their original CEO was absent, Drobo’s products turned more towards profitability, perhaps too soon for the company, as the products released during that period were less than stellar. We actually got a few of those Drobos in for review, but their performance was so inconsistent that we spent more time trying to figure out what was causing the issues than completing a review we could stand behind. With their founder back in the CEO chair, Drobo's path was turned back to its roots - making a good, fast, and low cost product for their customers. This was what they wanted to accomplish back in 2009, but in many ways the available tech was not up to speed yet. USB 2.0 was the fastest widely available standard, aside from iSCSI over Gigabit (but that was pricey to implement and appeared in the DroboPro). Nowadays things are very different. USB 3.0 controllers are vastly more compatible and faster than they used to be, as is SATA controller hardware and ARM microcontrollers. These developments would ultimately enable Drobo to introduce what they wanted to in the first place:

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This is the third generation 4-Bay Drobo. The 4-Bay model is what started it all for them, but was a bit underpowered and limited to USB 2.0 speeds. The second gen unit launched mid 2008, adding FireWire as a faster connection option, but it was still slower than most would have liked given its $500 price tag. This third generation unit promises to change all of that.

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USB is once again the only connectivity option, but this time it’s USB 3.0. There have previously been other 5-bay Drobos with this as an option (Drobo S, S gen 2, 5D, Mini), but many of those units saw compatibility issues with some USB 3.0 host controllers. We experienced some of these same frustrating incompatibilities first hand, and can confirm those frustrations. Drobo is putting that behind them with a revised chipset, and today we will put it all to the test.

Read on for our full review of the new Drobo!

December 29, 2014 | 09:22 AM - Posted by Mipo (not verified)

Personally I stay away from proprietary raid solutions.
If the hardware fails and the said hardware is older and not in production anymore then only Drobo is able to get the data back for mega dollars.
Few years back it has happened to a well known photographer, because he was all over social media. Then Drobo offered to get the data for free. But he wowed to never use such a solution anymor.

December 30, 2014 | 01:31 PM - Posted by Allyn Malventano

I think a lot of people fall into the trap of thinking RAID is a backup. It is not. No storage solution is bulletproof. Proprietary RAID solutions are ok so long as you diversify and have at least two full copies of your data. If yout get right down to it, even a single HDD is a 'proprietary solution' in that if it fails, your data is not coming back without some potentially expensive recovery efforts.

Drobo details some good backup regimes here.


December 28, 2015 | 04:54 PM - Posted by pete7201_X (not verified)

Wow... amazing that Drobo did that.

December 29, 2014 | 09:33 AM - Posted by Branthog

Boy are the two drobos I bought the worst investment I have ever made. I thought I'd take a short cut and wound up baying the price when I lost 9tb of data and found that the only available diagnostics for it are completely unreadable to the user.

December 29, 2014 | 11:04 AM - Posted by Anonymous (not verified)

Does this new version also limit you to a max 16TB volume?

December 30, 2014 | 01:14 PM - Posted by Allyn Malventano

Yes, but remember that is a 16 TiB (not TB) limit. On the 4-bay unit, with 6TB drives installed and default single parity in use, you get 3 x 5.45 TB (5.45 is the actual capacity of a '6TB' HDD) available, which works out to 16.34TB on the Drobo. That's just under the 2^44 (16 TiB) volume limit. If you were to go over this with larger drives in the future, you would have to create an additional volume to use that extra space.

December 29, 2014 | 02:36 PM - Posted by sean (not verified)

Right now my 2nd gen crashes over usb so now all I can do is read the NTFS data over firewire on my mac. Till I can save up enough for a synology the drobo holds my data hostage.

December 30, 2014 | 01:17 PM - Posted by Allyn Malventano

...or you can pay less for the newer Drobo (without drives) and simply move your existing drives over to it, and benefit from 2x the USB 3.0 speed as compared to what you will see from any gigabit connected NAS.

(also, be sure you are backing up to another place once you get it back up and running).

December 30, 2014 | 02:46 AM - Posted by Anonymous (not verified)

I had an earlier generation Drobo. It worked for a while, but its data rate was very low and after about a year it silently failed. It was completely bricked and totally unrecoverable.

Like Mipo, I now stay away from proprietary raid solutions. When they fail, your data is pretty much unrecoverable.

December 30, 2014 | 11:36 AM - Posted by Allyn Malventano

Not to discount you guys' experiences, but all of you appear to be "doing it wrong". Your data should not be held hostage by any single device, because your data should not be in only one place. *Any* storage device can fail over time (Synology included), and a RAID is not a backup (unless it's a second copy). Drobo is not exempt from the fact that computer hardware does not last forever. Additionally, data on NAS devices that are cloud enabled or otherwise made available online can be hacked or 'held hostage' in other ways. So to repeat, nobody should be putting all of their data on any single device with no other backup.

I've personally used a DroboPro for 5 years *as a backup* to a separate RAID and had no issue. Also, if you look at the update chart, any disk pack from a 4-bay 1st or 2nd gen drobo can be moved to the 3rd gen unit (meaning that your data is actually not hostage). Further, this new unit is selling for cheaper than most competing 4-bay NAS units, so if you're claiming to be stuck with your data held hostage on an older unit, this is your way to easily get it all back.

December 30, 2014 | 03:46 PM - Posted by Anregen (not verified)

bwahah! I imagine you doing air-quotes when saying: "doing it wrong".

Jokes aside, you're totally right. If your important data is only in one place, then you're holding yourself hostage.

January 2, 2015 | 08:19 AM - Posted by spigzone (not verified)

It may be a RAID isn't supposed to be a backup, but i suspect most non-professional Drobo buyers do just that. As a fixed income retirees non-professional I bought my Drobo gen 2 (for $340 on sale) specifically to take advantage of my existing drives and so the failure of one drive wouldn't cause any data loss. I will be buying a gen 3 and then a Seagate

I was a bit surprised at how brief your review was for such an important product.

I do have a question you could perhaps look into and resolve. Does Drobo play nicely with Spinrite? If I have a drive go bad can I remove it, run Spinrite to repair it, reinsert it and have Drobo retain all the data except for any bad sectors Spinrite finds and tags?

January 5, 2015 | 04:16 AM - Posted by Allyn Malventano

You can run tools like SpinRite so long as they are data agnostic (i.e. keep everything where it was and not try to rearrange anything). I would recommend doing that run with the Drobo powered down, as it will immediately try to start rebuilding with the remaining drives as soon as you remove a drive 'hot'.

I will say that with RAIDs or Drobos, it's often a better bet to simply run some sort of task that reads all data from the volume. That will effectively cause all drives to attempt to read all active data, which will force the drives to correct or reallocate any bad sectors they come across in the process.

Little known fact - no application (SpinRite included) can directly move a bad sector through a modern HDD's logic. All the application gets is what the drive reports, and in the case of a bad sector it gets the drive's best guess along with a flag that states it was not correctable in the case where there was not enough good data there to correct on its own. A program like SpinRite may make repeated attempts in the hopes of getting a good read, and it may even get lucky in doing so, but at the end of the day it is up to the hard drive logic itself to reallocate that sector to one of the spares. That process must take place within the drive as the table of remapped sectors is maintained within the drive and is generally not accessible or alterable without manufacturer specific tools. That's not to say SpinRite is not useful, but it's not as effective on modern drives as it was back in the day, and most of its functionality can now be accomplished by periodically reading all data from an array or individual drive.

March 25, 2015 | 01:48 AM - Posted by Flash (not verified)

Allyn, What "task" would you recommend that would read all the data? If I'm understanding you correctly, that approach forces the device to stumble onto bad data (bad sectors, ect.) and self correct. I've also been wondering if the Drobo can correct for bit-rot in the same sort of manner that a ZFS based filesystem can.

January 1, 2015 | 03:10 PM - Posted by Anonymous (not verified)

Any chance on mixed drive performance reviews? One of the main benefits of BeyondRAID is being able to mix and match different drive sizes as storage technology becomes cheaper, but from what I've seen it really hurts performance.

January 5, 2015 | 03:31 AM - Posted by Allyn Malventano

There are really too many combinations of drives to dive down that rabbit hole, but I can say that generally, mixed drive performance is going to be limited by the slowest installed drive. It's better to leave out that several year old drive that is only a small fraction of the capacity of the other drives, as it will just drag down the overall performance.

January 2, 2015 | 10:20 PM - Posted by MikeKV (not verified)

Forget Synology, Drobo, etc. I'll stick to a physical PC with Windows and Stablebit DrivePool. The drives behave just like the Drobo, the software is only $20 (assuming you already have a Windows machine), and the drives in the pool are NTFS, so if the PC dies you can take them out and stick them in any NTFS capable computer to recover your data.

January 5, 2015 | 03:28 AM - Posted by Allyn Malventano

I'm with you on all of the above except for one point. I'm testing out DrivePool myself, but a 4-bay Drobo is a more efficient use of space to get redundant storage (in single disk parity mode). Redundancy on DrivePool volumes behave like a RAID-1 mirror, so you need double the drives necessary, where on the Drobo you only need one drive of capacity donated to the cause of failure protection. It's not specific to Drobo - RAID-5 parity is always more capacity efficient than a RAID-1 mirror.

Also, Drobos are marketed more towards folks that don't have a PC lying around that they could fill with drives and have act as a DrivePool / NAS type of device.

January 3, 2015 | 10:19 AM - Posted by andrewk (not verified)

I agree with MikeKV. I run a windows box with a mix of 11 drives (5 internal 6 external usb) and a Drivebender pool. Ntfs drives, mirrored folders like the good old Windows home server. $20.

March 17, 2015 | 10:52 AM - Posted by Paulo Basseto (not verified)

Having a custom made NAS / Backup computer is always a plus for us who like to get our hands dirty, but you have to add to that $20 cost the cost of the machine, electricity and all 11 drives you added to your equation there.
Lets assume your drives are same size and brand, 2TB WD drives are still going for ~ $99,00. Give or take thats $1100,00 on drives alone... :-/
Plus there is applications and applications. I'm a wedding photographer. For me to have 2 NAS boxes sitting is unfeasible. I just dont have the shelf / storage real space for that on my office, and then comes the price again, that would double to a wopping $2200,00 just on drives.

Is drobo bullet proof? NO! I made the mistake of having a single Drobo 2nd Gen as a main backup and no other backups until the partition got corrupted. Im talking about wedding backups since 2005. I was extremely lucky to be able to recover 99% of that, and the 6 jobs I wasn't able to recover, I had already delivered to clients, so it was a matter of asking them a copy of their DVD's to add again to my array. But you cant beat its pricing point:

I now run 2 drobos (2nd gen and a 3rd gen) with goodsync one way backup keeping on site backup and crashplan for the offsite.
So simple math:
Drobo 2nd Gen: $300,00 (back in 2010)
Drobo 3rd Gen: $250,00
4 WD RED 3TB: $440,00
4 Seagate 2TB: $280,00

Thats the ~1270 bucks one box would cost, but getting 2 on site backup.

January 5, 2015 | 11:56 AM - Posted by JPC82 (not verified)

I have a Drobo 2, the one this is replacing and I completely agree with Allyn. You should never have your data only on a single device and expect RAID to protect you. RAID will fail at some point (Hardware, software or user issue). I have had mine fail from filesystem issues and format needed to fit it, but I still had my data or anything lost wasn't important enough to have a backup.

My experience with Drobo is mixed. It does most of what they said they would do, but not all.

One thing I would have liked to see is how the Drobo handles dealing with tons of small files all over the file system (thousands of files in thousands of folders). When I used to use my Drobo for storing TimeMachine and photo backups it would go from an ok ~15mb/s to a terrible 1-3mb/s. Since Drobo is data aware it has to keep track of all that data and the hardware wasn't able to keep up with all those files.

Firewire on my unit is basically useless and not much help from them. My older Mac (running 10.9) would complain with errors if I ran it over firewire and support never provided a good solution except for a special driver that also reduced the speed, so no real help. I had to stick to USB 2

I use it solely as a backup device to take a bunch of smaller drives and have it give me a single larger drive to backup to. I copy data to it in the background (since it is so slow) and try to backup larger files where possible to keep the file count down. For this it works well, but not really how they sold it.

I would consider a Drobo in the future but at the moment I just don't know since I had wanted to use it as a large working drive but as soon as I tried to actually use it and fill it with files the performance would just keep dropping.

January 6, 2015 | 10:06 PM - Posted by David Hill (not verified)

I bought the 5D about three years ago (maybe more) and have been very pleased with the solution. I also have a second (single disk) back up of my data which I keep at another location. I have had a couple of disk failures but both could not be easier to deal with (i.e. whack in a new HDD and let the Drobo do the rest!).

The only thing I would like is faster performance and I am wondering whether to buy a 5N or maybe see of anything new comes out at CES.

January 15, 2015 | 12:22 PM - Posted by minerva

Too bad it doesn't support ZFS. I am currently looking for an external HDD enclosure to expand my server.

January 30, 2015 | 04:54 PM - Posted by Mariano (not verified)


I am happy with my 2nd gen drobo, until 2 days ago.
2 drives showed like unreadable, were 2 of 2tb, so I took one out, put another and worked, the 2nd, one I replaced it for a 6tb drive, and even it recognizes it and shows it along teh other 2 of 2 tb and 1 of 4tb, still saying that i only have 8tb of capacity.

Don't understand it, how its that possible?

June 4, 2015 | 09:30 AM - Posted by GuyJr (not verified)

After calling Drobo, I loaded two 6 terrabyte drives in the Drobo. That went well.

Three items prompt the 1 star review.

1. Windows claims 15.9 TB capacity. It should claim less then 6 TB capacity. Clearly the Drobo firmware doesn't understand the windows interface. This product was released more than a year ago. This should have been fixed long ago.

2. The USB 3.0 specification supports transfer speeds up to 625 MB/s. The Drobo, as configured, supports only 40 MB/s. That is not what I purchased! Other reviewer's have reported drive incompatibility issues. This, again, links to a Drobo firmware or design issue. I see no reason to purchase different drives in the perhaps vain attempt for better throughput.

3. There are many other sour reviews echoing my sentiments.

So rather than waste more time and money on a poorly designed device, I'll simply sell it on ebay and move on.

March 20, 2016 | 07:16 AM - Posted by Anonymous (not verified)

i just recently had a free nas 2 of my 3 drives was not working anymore my data was gone but i did have it back up on my main pc.
this time around im buying a drobo i want to mix and match my drives so i can get bigger sizes when i can afford them cant do that with any other solution plus having my data proprietary sucks but at least i can get it back and able to transfer it to new drobos are nice remember a nas is all about keeping it safe if its at risk of loosing it and starting over its a total disaster.